Heat Transfer Fundamentals Concerning Quenching Materials in Cold Fluids

Abstract

The current chapter discusses three principles of heat transfer related to transient nucleate boiling process when any film boiling during quenching is completely absent. They include the duration of nucleate boiling establishment, surface temperature behavior during self-regulated thermal process, and generalized fundamental equation for evaluation of transient nucleate boiling length. In fact, majority of authors in their analytical and experimental investigations always considered three classical heat transfer modes: film boiling, nucleate boiling, and convection. It is shown in the chapter that the absence of film boiling process simplifies numerical and analytical calculations. It is very important to know that mentioned principles can be used for calculation of temperature fields and stresses and development of new technologies without performing costly experiments. Such an approach can be used for measuring different forms and sizes of quenched steel parts. It is stated that universal correlation for heating and cooling time evaluation, modified by proposed principles, can be widely used for recipes development when exploring new intensive quenching technologies. Examples of calculations are provided.